“Delivered” Depends On Context

Posted by J.D. FalkNovember 18, 2010

by J.D. FalkDirector of Product Strategy

Last week on IN the Know, Chad Malchow pointed out quite accurately that when an email sending system reports that a message has been ‘delivered,’ that may not be an accurate portrayal of the final destination of the message. “Typically,” he wrote, ” an Email Service Provider considers email to be ‘delivered’ whether it goes to the inbox or junk/bulk folder.”

To understand why that is, and why ‘delivered’ has been the term of art for so long, we just need to look at the email delivery process.

What you see happening in the chart (click to see it larger) may best be described as a transfer of responsibility. When the receiving system accepts the message from the sending system, the receiving system becomes responsible for that message.

The word ‘delivered’ does fit here, because the sending system has delivered the message to the receiving system. What the receiving system does with that message after accepting it is called “local delivery,” and (as far as the sender is concerned) takes place invisibly behind the scenes.

But the apparent confusion over the “delivered” metric may actually stem from the recipient experience, not the sender’s. Until about ten years ago, most users did not have different folders for different types of incoming mail. There was no spam folder, no priority inbox, nothing. Sure, there were filtering programs like procmail, and many geeks had (and still have) complex filtering schemes to separate discussion lists, automatic notifications, et cetera — but the majority of users had no idea that server-side filtering was even possible.

In that world, at that time, a message was either in the inbox or it hadn’t been delivered yet.

Today, almost all email users have a spam folder. It’s part of the collective consciousness. But that doesn’t change the basic nature of email, where a message is delivered from one system to another. That’s why Return Path has been championing a new term, “Inbox Placement Rate,” for measurement of messages placed in the recipient’s inbox folder. It’s far less confusing than trying to change the definition of a term that’s been around for decades.